Three-dimensional (3D) models of a building may be generated based on two-dimensional (2D) digital images taken of the building. The digital images may be taken via aerial imagery, specialized-camera equipped vehicles, or by a user with a camera. The 3D building model is a digital representation of the physical, real-world building. An accurate 3D model may be used to derive various building measurements or to estimate design and renovation costs.
However, generating a 3D model of a building requires significant time and resources. If only a particular measurement, or set of measurements, is needed, it would be inefficient to generate a 3D model of the whole building in order to derive the particular measurement or measurements.
Rather than generating a 3D model to derive a measurement, the measurement may be estimated using a machine learning model. For example, the roof area of a building may be estimated based on the roof outline of the building. An outline of the roof of the building may be generated using one or more images that depict an overhead view of the building, such as orthographic or oblique images.
However, overhead images must be captured using specialized equipment or licensed from a 3rd-party provider. Thus, overhead images may be difficult or costly to obtain. Additionally, the overhead view of a building may not fully describe features such as roof overhangs, wall to roof features, and etc. Furthermore, overhead imagery might be obstructed by foliate, cloud cover, neighboring buildings, and etc. Thus, a method for generating an outline of a building using only ground level images, or images taken at different heights and angles, is desired. Images taken at different heights may include, for example, images from a hand-held camera from a person standing on a roof or images from a remotely-operated camera capable of taking images at different heights.
The approaches described in this section are approaches that could be pursued, but not necessarily approaches that have been previously conceived or pursued. Therefore, unless otherwise indicated, it should not be assumed that any of the approaches described in this section qualify as prior art merely by virtue of their inclusion in this section.